1. Field of the Invention
This invention relates to a device or apparatus for manipulating matter within a confined or inaccessible space, especially during surgery in a living body.
2. Description of the Prior Art
Matter may be manipulated in such circumstances in various ways, for example by application of a ligature, by suturing, by cutting with a knife or scissor action, or by capture and retrieval in devices such as screens, baskets, barriers, pouches, or retractors. Such manipulation may be difficult when operating in the confined space of a very deep wound or through a small arthroscopic or other endoscopic incision or body aperture.
Many forms of apparatus for performing surgical operations have been proposed previously using flexible steel wires which spring apart when extended from the distal end of a tube and which can be brought together again on withdrawal back into the tube. Examples of such known devices may be seen in U.S. Pat. Nos. 2,114,695, 2,137,710, 2,670,519, 3,404,677, 4,174,715, 4,190,042, 4,222,380, 4,249,533, 4,347,846, 4,655,219, 4,691,705, 4,741,335, 4,768,505 and 4,909,789. However, these devices may not be completely satisfactory for various reasons, especially after repeated use or long storage which may fatigue the materials used.
Attempts have been made to use shape memory metals in surgical apparatus, but these suffer from inconvenience and from the risk of damage to living tissues resulting from the need either to cool the memory metal while positioning it in the body so that body heat thereafter actuates the shape memory effect, or to heat the metal above body temperature to actuate it after positioning. Examples of such attempts are described in U.S. Pat. Nos. 4,509,517, 3,868,956 and 4,425,908.